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BootROM
Boot ROM is a piece of read-only memory (ROM) that is used for booting a computer system. It contains instructions that are run after the CPU is reset to the reset vector, and it typically loads a bootloader. There are two types of boot ROM: a mask boot ROM that cannot be changed afterwards, and a writable boot ROM such as an EEPROM or a flash memory chip. Purpose Upon power up, hardware usually starts uninitialized. To continue booting, the system may need to read a bootloader from some peripheral device. It is often easier to implement routines for reading from external storage devices in software than in hardware. A boot ROM provides a place to store this initial loading code, at a fixed location immediately available to the processor when execution starts. Operation The boot ROM is mapped into memory at a fixed location, and the processor is designed to start executing from this location after reset, according to the processor's reset vector. The boot ROM is either pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Read-only Memory
Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. Data stored in ROM cannot be electronically modified after the manufacture of the memory device. Read-only memory is useful for storing software that is rarely changed during the life of the system, also known as firmware. Software applications, such as video games, for programmable devices can be distributed as ROM cartridge, plug-in cartridges containing ROM. Strictly speaking, ''read-only memory'' refers to hard-wired memory, such as diode matrix or a #Solid-state ROM, mask ROM integrated circuit (IC), that cannot be electronically changed after manufacture. Although discrete circuits can be altered in principle, through the addition of Jump wire, bodge wires and the removal or replacement of components, ICs cannot. Correction of errors, or updates to the software, require new devices to be manufactured and to replace the installed device. Floating-gate ROM semiconductor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MicroSD
Secure Digital (SD) is a proprietary hardware, proprietary, non-volatile memory, non-volatile, flash memory card format developed by the SD Association (SDA). Owing to their compact size, SD cards have been widely adopted in a variety of portable consumer electronics, including digital cameras, camcorders, video game consoles, mobile phones, action cameras, and Unmanned aerial vehicle, camera drones. The SD format was introduced in August 1999 by SanDisk, Panasonic (then known as Matsushita), and Kioxia (then part of Toshiba). It was designed as a successor to the MultiMediaCard (MMC) format, introducing several improvements aimed at enhancing usability, durability, and performance, which contributed to its rapid emergence as an industry standard. To manage the licensing and intellectual property rights related to the format, the three companies established SD-3C, LLC. In January 2000, they also founded the SDA, a non-profit organization dedicated to developing and promoting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Engineering
Reverse engineering (also known as backwards engineering or back engineering) is a process or method through which one attempts to understand through deductive reasoning how a previously made device, process, system, or piece of software accomplishes a task with very little (if any) insight into exactly how it does so. Depending on the system under consideration and the technologies employed, the knowledge gained during reverse engineering can help with repurposing obsolete objects, doing security analysis, or learning how something works. Although the process is specific to the object on which it is being performed, all reverse engineering processes consist of three basic steps: information extraction, modeling, and review. Information extraction is the practice of gathering all relevant information for performing the operation. Modeling is the practice of combining the gathered information into an abstract model, which can be used as a guide for designing the new object or syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Map
In computer science, a memory map is a structure of data (which usually resides in memory itself) that indicates how memory is laid out. The term "memory map" has different meanings in different contexts. #It is the fastest and most flexible cache organization that uses an associative memory. The associative memory stores both the address and content of the memory word. #In the boot process of some computers, a memory map may be passed on from the firmware to instruct an operating system kernel about memory layout. It contains the information regarding the size of total memory, any reserved regions and may also provide other details specific to the architecture. #In virtual memory implementations and memory management units, a memory map refers to page tables or hardware registers, which store the mapping between a certain process's virtual memory layout and how that space relates to physical memory addresses. #In native debugger programs, a memory map refers to the mapping betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exploit (computer Security)
An exploit is a method or piece of code that takes advantage of Vulnerability (computer security), vulnerabilities in software, Application software, applications, Computer network, networks, operating systems, or Computer hardware, hardware, typically for malicious purposes. The term "exploit" derives from the English verb "to exploit," meaning "to use something to one’s own advantage." Exploits are designed to identify flaws, bypass security measures, gain unauthorized access to systems, take control of systems, install malware, or data breach, steal sensitive data. While an exploit by itself may not be a malware, it serves as a vehicle for delivering malicious software by breaching security controls. Researchers estimate that malicious exploits cost the global economy over US$450 billion annually. In response to this threat, organizations are increasingly utilizing cyber threat intelligence to identify vulnerabilities and prevent hacks before they occur. Description Expl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chain Of Trust
In computer security, a chain of trust is established by validating each component of hardware and software from the end entity up to the root certificate. It is intended to ensure that only trusted software and hardware can be used while still retaining flexibility. Introduction A chain of trust is designed to allow multiple users to create and use the software on the system, which would be more difficult if all the keys were stored directly in hardware. It starts with hardware that will only boot from software that is digitally signed ( bootloader). The signing authority will only sign boot programs that enforce security, such as only running programs that are themselves signed, or only allowing signed code to have access to certain features of the machine. This process may continue for several layers. This process results in a chain of trust. The final software can be trusted to have certain properties because if it had been illegally modified its signature would be inva ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Root Of Trust
In cryptographic systems with hierarchical structure, a trust anchor is an authoritative entity for which trust is assumed and not derived. In the X.509 architecture, a root certificate would be the trust anchor from which the whole chain of trust is derived. The trust anchor must be in the possession of the trusting party beforehand to make any further certificate path validation possible. Most operating systems provide a built-in list of self-signed root certificates to act as trust anchors for applications. The Firefox Mozilla Firefox, or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. It uses the Gecko rendering engine to display web pages, which implements curr ... web browser also provides its own list of trust anchors. The end-user of an operating system or web browser is implicitly trusting in the correct operation of that software, and the software manufacturer in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Certificate Authority
In cryptography, a certificate authority or certification authority (CA) is an entity that stores, signs, and issues digital certificates. A digital certificate certifies the ownership of a public key by the named subject of the certificate. This allows others (relying parties) to rely upon signatures or on assertions made about the private key that corresponds to the certified public key. A CA acts as a trusted third party—trusted both by the subject (owner) of the certificate and by the party relying upon the certificate. The format of these certificates is specified by the X.509 or EMV standard. One particularly common use for certificate authorities is to sign certificates used in HTTPS, the secure browsing protocol for the World Wide Web. Another common use is in issuing identity cards by national governments for use in electronically signing documents. Overview Trusted certificates can be used to create secure connections to a server via the Internet. A certificate is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Public Key Infrastructure
A public key infrastructure (PKI) is a set of roles, policies, hardware, software and procedures needed to create, manage, distribute, use, store and revoke digital certificates and manage public-key encryption. The purpose of a PKI is to facilitate the secure electronic transfer of information for a range of network activities such as e-commerce, internet banking and confidential email. It is required for activities where simple passwords are an inadequate authentication method and more rigorous proof is required to confirm the identity of the parties involved in the communication and to validate the information being transferred. In cryptography, a PKI is an arrangement that ''binds'' public keys with respective identities of entities (like people and organizations). The binding is established through a process of registration and issuance of certificates at and by a certificate authority (CA). Depending on the assurance level of the binding, this may be carried out by an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hash Function
A hash function is any Function (mathematics), function that can be used to map data (computing), data of arbitrary size to fixed-size values, though there are some hash functions that support variable-length output. The values returned by a hash function are called ''hash values'', ''hash codes'', (''hash/message'') ''digests'', or simply ''hashes''. The values are usually used to index a fixed-size table called a ''hash table''. Use of a hash function to index a hash table is called ''hashing'' or ''scatter-storage addressing''. Hash functions and their associated hash tables are used in data storage and retrieval applications to access data in a small and nearly constant time per retrieval. They require an amount of storage space only fractionally greater than the total space required for the data or records themselves. Hashing is a computationally- and storage-space-efficient form of data access that avoids the non-constant access time of ordered and unordered lists and s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EFuse
In computing, an eFuse (electronic fuse) is a microscopic fuse put into a computer chip. This technology was invented by IBM in 2004 to allow for the dynamic real-time reprogramming of chips. In the abstract, computer logic is generally "etched" or "hard-wired" onto a chip and cannot be changed after the chip has finished being manufactured. By utilizing a set of eFuses, a chip manufacturer can allow for the circuits on a chip to change while it is in operation. Mechanism of action eFuses can be made out of silicon or metal traces. In both cases, they work (blow) by electromigration, the phenomenon where electric flow causes the conductor material to move. Although electromigration is generally undesired in chip design as it causes failures, eFuses are made of weak traces that are designed to fail before others do. Uses eFuses were initially marketed by IBM as a way to provide in-chip performance tuning. If certain sub-systems fail, or are taking too long to respond, or a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
